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I can have a tab running from one of my bars to the shock mount for sure. I hadn't planned on it, but I want it all fairly removable anyway.

The bolts in those pictures are the stock seat latch bolts. However I have to find some bolts for the seat belt mount point and child seat mount point. Would Grade 8.8 or Grade 10.9 bolts be preferable? I guess might as well go highest grade.

It doesn't seem like it's possible that it is there for any sort of structural strength but I'm not sure? Maybe it prevents buckling at the center of that beam? It is way heavier than it needs to be for anything structural, and there is foam between it and where it contacts the roof sheet.

More bracing. I got 90% of the way through twin to this one on the other side but it started POURING rain. The bay flooded and I decided I didn't need to be welding while standing in a puddle. They aren't quite identical as I'm doing a lot of Eyeball Engineering, off by about 1/4 inch in space. Right one is farther back from the shock tower than the left one. I don't think it's hugely important....

What on earth that hunk of metal does is still baffling me. Do I really need it? It's heavy and I would like to cut the weight out. I bet if anyone has removed it, it's that crazy nordic guy...

[IMG]What on earth that hunk of metal does is still baffling me. Do I really need it? It's heavy and I would like to cut the weight out. I bet if anyone has removed it, it's that crazy nordic guy...

It's for vibration damping. The mass of an assembly is related to its natural frequency. They probably had an issue with vibration in the roof at some frequency and the hack way of fixing this is to increase the mass of the assembly.

I'm mostly doing this because I'm very nervous to put that quarter panel back on and want more practice. It is a refreshing change of pace though.

Originally Posted by SilverMk2

It's for vibration damping. The mass of an assembly is related to its natural frequency. They probably had an issue with vibration in the roof at some frequency and the hack way of fixing this is to increase the mass of the assembly.

Yeah the stock seat latch bolts are only the first level of strength. The metric grading system is different, the FSRM covers it and shows what the different markings on the factory bolts mean. 8.8 is weak sauce, 10.9 isn't bad. 12.9 is king, but can be hard to find a lot of bolts in.

Got some bolts today. Shockingly the local Home Depot actually had a decent selection of grade 10.9 for the seat latch mount and the child seat anchor.

Then grabbed some Grade 8 shoulder bolts for attaching my heim joints to make the structure removable.

Only issue was finding Grade 8 nuts for the heim joints I bought off fleabay. Turns out not a lot of places carry 1/2 - 20 nuts. I found some Grade 5, which I think might be adequate for a couple reasons.
- easiest way to attach the heim to the tubing is to weld the nut onto a cap at the end of the tube, welding is going to damage any heat treatment on the bolts I pick anyway.
- grade 8 apparently doesn't weld as easy - becomes more brittle.
- 1/2' is pretty large so I think the overall size, compared to like the M6 bolts, is going to be a primary strength of the joint compared to just a stronger bolt in the case of the other mounting points.

It's been too dang hot here in VA to do some fabricating. Shed today read 92 degrees, 60% humidity and when you get the welder going that's way too hot for me.

It's coming along. Here is one side, it definitely warped a little when I was welding in that reinforcement place, as now you have to pull it a little to get all three bolts in, but they still go in and can be tightened down. I need to take some time to think about how I want to tie in the third leg of the triangle and possibly integrate the shock tower.
Hey Fiend, for the tower could I just have a plate running across it that the shock itself bolts through? I can't think of any other way to do it really.

Here is a crappy cardboard mockup of how I'm thinking about tying this all together. I'd like that last link between the seat latch and the frame rail, just to make sure it's triangulated and the frame rail point doesn't rotate.

The only way I can think to tie in the shock mount is a plate tied into the seat belt - frame rail tube. Then to keep it from excessively bending and only minorly bending, T it off to the same tube. It will still be in the worst possible spot in terms of leverage on the tube but I can't think of many other options and it should be very effective in preventing up/down tower motion. Wont be effective against fore and aft motion, and slightly better at left to right. The wider the T the better.